docs: fix and expand DeFi Wrapper disconnect guide

[itaven]

Summary

• Add "Before you start" section — dw info <poolAddress> to get all contract addresses upfront
• Extend Step 1 role table: add VOLUNTARY_DISCONNECT_ROLE, COLLECT_VAULT_ERC20_ROLE, MANAGER_ROLE with context on which are optional and which are pre-granted
• Step 3: replace prose with actual CLI commands for finalization verification; remove nonexistent unfinalizedStethShares command
• Step 5: expand undercollateralized user handling — add full CLI commands, dry-run note, oracle requirement warning, and maxLossSocializationBP explanation
• Step 7: remove redundant "get Distributor address" step (now covered by dw info), renumber 7.x steps accordingly; clarify wstETH conversion rationale; add unit guidance for safe-transfer-erc20 amount arg
• Fix CLI command names: trigger-v-w → trigger-validator-withdrawal, stv-steth w pause-deposits → stv w pause-deposits
• Add stvStrategyPool claiming flow via CLI: proxy-of → claim --recipients <proxy> → safe-transfer-erc20
• Improve "Claiming with CLI" section: add fallback note if UI unavailable, clarify proxy distribution for stvStrategyPool